1. Field of the Invention
The present invention relates generally to "preservative-free" syrup and beverage compositions and a method of making them, that is, syrup and beverage compositions containing no conventional chemical food preservatives, such as sorbic, benzoic and propinoic acids and the alkali metal salts thereof. More particularly, the invention relates to cold-filled microstable, preservative-free soft drinks having desirable taste and drinkability properties.
2. Description of Related Art
In order to achieve an adequate unrefrigerated shelf-life, conventional chemical preservatives, heat treatment, or a combination of both, typically has been used to produce microstable beverages (i.e., beverages stabilized against microbiological spoilage).
Heat treatment or thermal processing steps, such as hot filling and tunnel pasteurization, have been used to reduce yeast, mold and microbial growth in food and beverage products. For example, U.S. Pat. No. 4,830,862 to Braun et al. discloses the use of pasteurization in the production of fruit juice beverages as well as the use of suitable preservatives in carbonated beverages. U.S. Pat. No. 4,925,686 to Kastin discloses a heat-pasteurized freezable fruit juice composition which contains sodium benzoate and potassium sorbate. However, such heat treatments have various disadvantages, such as consumption of energy and time as well as deleterious effects on the organoleptic properties of the thermally-processed products.
Chemical preservatives have long been used as another means of deterring microbial growth in beverages, thus enhancing product shelf-life. Conventional chemical food preservatives, i.e., those chemical compounds which are now classified and labelled as food preservatives under U.S. regulations, include sodium and potassium benzoate, sodium and potassium sorbate, and the like.
For example, U.S. Pat. Nos. 4,551,342 and 4,737,375 to Nakel et al. teach the use of sodium and potassium salts of benzoic acid to preserve the beverage systems exemplified therein. U.S. Pat. No. 4,996,070 to Nafisi-Movaghar lists sodium benzoate, potassium sorbate and alkyl parabens as examples of anti-microbial agents. U.S. Pat. No. 5,021,251 to McKenna et al. similarly discloses the use of sodium benzoate as a mold inhibitor.
"Clearly Canadian" and "Nordic Mist" are beverage products which contain water, a sweetener, natural flavor, and sodium or potassium benzoate as a preservative. A typical "Nordic Mist" composition includes: pure sparkling water, high-fructose corn syrup, citric acid, natural flavor and potassium benzoate. A "Clearly Canadian" composition typically includes the following ingredients: Canadian water, carbon dioxide, sugar, citric acid, natural flavor and sodium benzoate.
Although conventional chemical preservatives have been effective against microbial spoilage in beverages, due to growing consumer concern regarding product health attributes, there has been a desire for beverages free of these chemical food preservatives.
Some preservative-free food products have been developed. For example, certain additives have been disclosed as helping inhibit spoilage of food products. U.S. Pat. No. 3,681,091 to Kohl et al. relates to retarding spoilage of food products by means of polyphosphates. U.S. Pat. No. 4,534,991 to Kryger discloses the addition of an aseptic flavor system containing alcohol added to a previously pasteurized juice.
Certain systems containing acids have also been developed for helping preserve specific food products. U.S. Pat. No. 4,145,451 to Oles refers to a preservation system containing acetic acid and phosphoric acid for low-acid food products, specifically, mayonnaise, salad dressings and the like. U.S. Pat. No. 4,927,657 to Antaki et al. similarly refers to salad dressings preserved with buffered systems of phosphoric/acetic acids, acetic acid, acetic/fumaric acids, phosphoric/acetic/lactic acids, phosphoric/acetic/citric acids or phosphoric/lactic acids. Although such acid preservation systems have been developed for certain foodstuffs, these systems are not appropriate for beverages which require distinct organoleptic attributes.
Systems have also been developed for preserving beverages. U.S. Pat. No. 4,756,919 to Cirgiano et al. discloses beverage compositions employing a preservation system containing fumaric acid, but the exemplary compositions also contain sodium benzoate.
Cola-type carbonated beverages have been developed containing no conventional preservatives, which are flavored using emulsions of cola flavor oil. One known cola product contains phosphoric and citric acids, has a pH of 2.5 and a TA (titratable acidity) of 12.5, and is carbonated with 3.4 volumes of CO.sub.2 (i.e., 3.4 liters of CO.sub.2 per liter of beverage). Another known cola product contains phosphoric acid and 3.6 volumes of CO.sub.2, and has been found to have a pH of 2.5 and a TA of 13. Many consumers, however, desire non-preserved beverages which are not of the conventional cola type, such as beverages which have attributes of sports-drink type beverages, e.g., smoothness, nutritional content, citrus/fruit taste, etc.
Another product which contains no conventional chemical food preservatives is "Enduro," which is a carbonated beverage containing malic acid. Analysis of "Enduro" shows that this product has a pH of 2.7 and a TA of 30. Although "Enduro" is preservative-free, it suffers from various drawbacks, such as a relatively harsh taste due to the high amount of malic acid.
Therefore, it can be seen that it would be advantageous to provide a microstable, cold-filled soft-drink type beverage which has desirable attributes, such as being preservative-free and highly drinkable.